WASHINGTON (CNN) -- Sen. Hillary Clinton raised $27 million in the third quarter for her 2008 Democratic bid for the White House, a Clinton aide said Tuesday.

Presidential hopeful Sen. Hillary Clinton raised $27 million in the third quarter, a Clinton aide said.

All but $5 million of Clinton's funds can be spent trying to win the Democratic presidential nomination in the primaries, the aide said.

More than 100,000 new donors contributed to the New York Democrat, the aide said.

Clinton outpaced Sen. Barack Obama over the last three months, a reversal of positions from the second quarter.

The Obama campaign announced Monday the Illinois Democrat raised at least $20 million for his presidential campaign during the third quarter. All but about $1 million of Obama's contributions can be used in the primary fight.

In the second quarter, he shattered fundraising records by reporting he raised $32.5 million, $31 million of which he can use in his bid for the Democratic nod.

Clinton raised $27 million during this same period; all but $6 million can be used in the primaries.

Campaign finance laws limit the amount an individual can contribute to a candidate during the primary cycle to $2,300. At the same time, individuals can contribute another $2,300 to a candidate for the general election.

Campaigns often report the total of contributions for the primary and general cycles during a quarter, even though general election contributions can't be used immediately to buy ads or hire staff.

"Many in Washington have spent the last weeks declaring the outcome of this race to be preordained and the primary process a mere formality," said Obama campaign chief David Plouffe in a veiled reference to Clinton, the front-runner for the Democratic presidential nomination in most national polls.

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"Yet, in this quarter alone, 93,000 more Americans joined our campaign, because they desire real change and believe Barack Obama is the one candidate who can deliver it," Plouffe said. "This grass-roots movement for change will not be deterred by Washington conventional wisdom, because in many ways it is built to challenge it."

Obama's campaign said the senator has raised at least $74.9 million in primary funds so far this year from 352,000 donors.

In a conference call Monday, John Edwards' campaign announced the former U.S. senator from North Carolina raised $7 million during the third quarter.

Edwards, the party's 2004 vice presidential nominee, said last week he would accept public financing for the primary and general election campaigns, challenging Clinton and Obama to do the same.

Edwards' deputy campaign manager, Jonathan Prince, said the campaign has $12 million in cash. Prince said public funding will add $10 million to its totals.

Edwards has raised more than $30 million so far, and the campaign is on the right track to reaching its goal of $40 million by January, Prince said.

Crediting the campaign's aggressive grass-roots outreach, Prince said Edwards received donations from 150,000 Americans, with 97 percent of contributions less than $250.

Edwards raised more than $9 million in the second quarter.

On Sunday, New Mexico Gov. Bill Richardson reported campaign contributions of $5.2 million for the third quarter, which his campaign said supports his claim that he is a top-tier candidate.

"This figure obviously separates us from the second-tier candidates and makes clear this is a four-person race," Richardson's campaign said.

Most political observers put Clinton, Obama and Edwards as the first-tier candidates for the Democratic nomination.

Though $5.2 million is down from the $7 million reported in the second quarter, the Richardson campaign touted it as "a strong showing in a historically difficult fundraising period."

"Most importantly, this amount ensures we will have the resources we need to compete in the early states like Iowa, New Hampshire, Nevada and South Carolina," it said. "We have strong organizations in those states and continue to expand our field operations by adding staff and opening new offices."

The campaign did not disclose how much it had spent during the quarter or how much cash it had left. Candidates have until October 15 to file a full report with the Federal Election Commission.

On the Republican side, former New York Mayor Rudy Giuliani and former Massachusetts Gov. Mitt Romney are expected to battle again for the top spot. Romney raised nearly $35 million so far this year, with Giuliani $1.5 million behind.

Sources close to the Giuliani campaign said their candidate expects to be atop the pack for the third quarter.

Among the GOP candidates, former Sen. Fred Thompson will have his numbers closely scrutinized. Thompsonraised more than $8 million for his late-starting presidential campaign in the past three months, a Thompson campaign source said Monday.

Thompson's upcoming FEC report also will show 70,000 donors have contributed to the Tennessee Republican in the third quarter, according to the source, who requested anonymity because the campaign has not officially released the information.

The actor, a former "Law & Order" star, formally entered the presidential race last month, but he has been raising money since June. Thompson raised close to $3.5 million from about 9,000 donors in June, the final month of the second quarter.

Sen. John McCain of Arizona is expected to show he raised more than $5 million this quarter, but a McCain adviser said recent poll numbers in New Hampshire and a busy fundraising schedule next month show the campaign has "some life."

McCain raised $24.5 million the first two quarters of the year but spent nearly all of the funds raised.